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Generated on: July 20, 2026 at 09:33 PM

Countertop Square Footage Calculator

Inputs

Run 1 length2.4 m
Run 1 depth0.64 m
Run 2 length0 m
Run 2 depth0.64 m
Waste allowance10 %

This is an estimate based on rectangular runs and a typical waste allowance. Actual material depends on slab size, seam placement, cut-out count, edge profile, and pattern matching. For natural stone, the fabricator measures the finished template and may need a larger slab to keep veining consistent, so confirm quantities before ordering.

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Construction & DIY

Countertop Square Footage Calculator

Work out the area of a kitchen or bathroom countertop from one or two rectangular runs, with a waste allowance, so you can order slab, laminate, or solid surface.

Inputs

%
0 – 50 %

Results

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Details

Two runs total ... of countertop, or ... once a 10 % waste allowance is added.

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Countertop Square Footage

A countertop is ordered by area, and the area is set by the size of each rectangular run of counter plus a waste allowance for cut-outs and seams. This calculator adds up one or two runs — enough for most straight, L-shaped, and U-shaped kitchens — and converts the total into the area to order.

Adding up the runs

Each run is a rectangle, so its area is the length along the wall times the front-to-back depth, including the overhang:

A1=L1 D1A2=L2 D2\begin{aligned} A_1 &= L_1 \, D_1 \\ A_2 &= L_2 \, D_2 \end{aligned}

The total is the sum of the runs, and a waste fraction is added for sink and cooktop cut-outs, seam matching, and breakage during fabrication:

A=A1+A2Aw=A (1+k)\begin{aligned} A &= A_1 + A_2 \\ A_w &= A \, (1 + k) \end{aligned}

where kk is the waste fraction. For a single straight counter, leave the second run length at zero.

Worked example

Consider an L-shaped counter: a 2.4 m main run and a 1.6 m return, both 0.64 m deep, with a 10% waste allowance:

A=2.4×0.64+1.6×0.64=1.536+1.024=2.56Aw=2.56×1.10=2.82\begin{aligned} A &= 2.4 \times 0.64 + 1.6 \times 0.64 = 1.536 + 1.024 = 2.56 \\ A_w &= 2.56 \times 1.10 = 2.82 \end{aligned}

So the counter is about 2.56 m² of finished surface, and roughly 2.82 m² should be ordered.

Consider an L-shaped counter: an 8 ft main run and a 5.25 ft return, both 25 in (about 2.08 ft) deep, with a 10% waste allowance:

A=8×2.08+5.25×2.08=16.7+10.9=27.6Aw=27.6×1.10=30.3\begin{aligned} A &= 8 \times 2.08 + 5.25 \times 2.08 = 16.7 + 10.9 = 27.6 \\ A_w &= 27.6 \times 1.10 = 30.3 \end{aligned}

So the counter is about 27.6 sq ft of finished surface, and roughly 30 sq ft should be ordered.

Choosing inputs

Measure the depth to the front edge of the finished counter, not the cabinet face, so the overhang is included. The waste allowance is the input most worth adjusting: a plain laminate top with one sink needs little, while a natural-stone slab with a directional vein that has to match across a seam can justify 15% or more. Because slabs come in fixed sizes, a fabricator may still need a larger slab than the bare area suggests.

For the tile backsplash above the same counter, see Tile Calculator.

Frequently Asked Questions (FAQ)

How do I measure countertop area?

Break the counter into rectangles, measure the length and depth of each, multiply to get the area of each rectangle, and add them up. An L-shaped counter is two rectangles; a U-shaped counter is three, though two runs cover most kitchens if you measure the longest leg as one rectangle and the rest as the other. Include the overhang in the depth, since the slab has to cover it.

How much waste should I add for countertops?

About 10% suits most slab and solid-surface jobs. Sink and cooktop cut-outs, seam matching on patterned stone, and breakage during fabrication all consume material beyond the finished area. Busy veining or a directional pattern that has to line up across a seam can push the allowance to 15% or more.

Do I include the overhang in the depth?

Yes. The slab has to span the full front-to-back distance, including the lip that overhangs the cabinet face — usually about an inch and a half. Measuring to the front edge of the finished counter rather than the cabinet gives the depth the fabricator needs.

Disclaimer

This is an estimate based on rectangular runs and a typical waste allowance. Actual material depends on slab size, seam placement, cut-out count, edge profile, and pattern matching. For natural stone, the fabricator measures the finished template and may need a larger slab to keep veining consistent, so confirm quantities before ordering.

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